Rollers crimpers have been used in conservation agriculture to terminate cover crops; however, excessive vibration generated by the original straight-bar roller design has delayed adoption of this technology in the United States. To avoid excessive vibration, producers generally reduce operating speeds that increase the time needed to perform the field operation. The objectives of this research were to identify roller crimper designs that terminated rye cover crops consistently, resulted in soil moisture conservation after use, and minimized vibrations when operated in the field. Six different roller types were developed and tested at 3.2 and 6.4 km h−1 in Alabama field experiments during the 2006, 2007 and 2008 growing seasons. All roller types were used alone and one also in combination with glyphosate. Rye mortalities were evaluated 1, 2 and 3 weeks after rolling and compared with the check (non-rolled standing rye). Soil volumetric moisture content (VMC) was measured at the day of rolling, and then at 1, 2 and 3 weeks after rolling. Vibration was measured on the rollers' and tractor's frames during operation. Mortality for rolled rye 2 weeks after rolling was at least 98% compared with 96% for the check in 2006, 93% for rolling compared with 75% for the check in 2007, and 94% for rolling compared with 60% for the check in 2008 (P<0.10). There were no consistent differences in rye mortality across roller types (without glyphosate) and speeds. VMC for soil in non-rolled rye plots was consistently lower than in rolled rye plots, averaging 3% compared with 7% 2 weeks after rolling in 2006, and 4% compared with 8% in 2008. During 2007, VMC was affected by severe drought conditions, and differences between roller treatments were detected but minor. The straight-bar roller generated the highest vibration on the tractor's frame at 6.4 km h−1 (0.71 m s−2, RMS), which exceeded International Standards (International Standard Office (ISO)). At 6.4 km h−1, new roller designs generated significantly lower acceleration levels from 0.12 to 0.32 m s−2 on the tractor's frame and were below detrimental effects on health ‘health limits’ classified by ISO. Overall, 2 weeks after rolling, all roller designs effectively terminated rye above 90%, which is the recommended termination level of rye to plant a cash crop into residue mat, while protecting soil surface from water loss. New roller designs generate less vibration than the original design and can be used safely at higher operating speeds.

For a long time pesticides attracted interest from the Vietnamese governments and farmers for their positive effects in protecting crop yield losses resulting from pests and other plant diseases. Recently, the negative effects of pesticides on human health, natural food chains and the environment are increasingly being taken into account by both state and non-state actors. Striking a balance between positive and negative effects is complicated as, most likely, pesticides will continue to maintain their vital role in an agriculture-based country such as Vietnam. However, recently a shift can be noticed in farmers' selection and application of pesticides, initiated mainly by farmers themselves and to a lesser extent also by other actors such as the government, pesticide companies and distributors. This article provides an empirical insight into this shift, based on the results from research in four provinces in the Red River Delta. Possible implications for policies toward greening pesticide handling practices in vegetable production are drawn, such as removing inexpensive pesticides (often associated with high toxicity) from the market, giving technical training on pesticide selection and use to farmers, and reconsidering the role different actors can play in future safe vegetable production programs.

This work presents the results of a three-year field study of agroecosystems designed to restore soil organic matter (SOM) to degraded soils of the Georgia Piedmont. The systems combine a suite of management practices previously demonstrated to increase SOM when studied individually, and examine the effects of these techniques when used in combination in a cropping systems context on soil characteristics, crop production and weed biomass. The systems' components include organic management, alley cropping with perennial legumes, conservation tillage, use of winter cover crops, straw mulch and two compost application rates. Vegetable crops grown were a rotation of okra, hot pepper and a corn and winter squash intercrop. The systems were not able to maintain soil C or N without the addition of compost. Systems incorporating alley cropping, organic management, conservation tillage and compost maintained soil C, and increased in soil C when mulch was not applied. In organic, conservation tillage without alley cropping, soil C did not change significantly, even with annual 44.8 Mg ha−1 of compost additions. Patterns for soil N followed those of soil C. The study demonstrated that alley cropping can maintain and sequester soil C and N beyond organic conservation tillage alone, and more than conventionally tilled, chemically fertilized treatments. Crop yields did not vary by treatment due to high variation within treatments. Winter cover crop residue provided an effective weed barrier for 4 to 6 weeks in the spring, but additional hand weeding was required throughout the summer. The results of this systems-level study demonstrated interactions between management practices when used in combination that would not have been observed when studied individually. It also demonstrates that agroforestry techniques, conservation tillage and compost applications can increase soil C in degraded, clayey soils while they are in cultivation.

Using actual retail purchases from the 2006 Nielsen Homescan panel data, we estimate a hedonic model on price premiums and discounts associated with household characteristics, market factors, and product attributes focusing on the organic attribute for fluid milk. The organic attribute carries a significant price premium, which is largest of all product attributes considered in this study. Further, additional price variations among organic milk are observed for differences in fat content, container size and branding. Specifically, the results suggest that organic price premiums for half-gallon milk range from $1.23 for whole private label organic milk (60–68% above conventional counterpart) to $1.86 for nonfat/skim-branded organic milk (89–109% above conventional counterpart). The study also found that milk sold in a discount store (i.e., supercenter or club warehouse) was price 13 cents per half gallon, or 7.4%, below milk sold through other venues, and that milk on sale was priced 26 cents per half gallon, or 14.3%, less than the regular average price. Although household characteristics exert little influence on price relative to product attributes and market factors, the study does find that unmarried households and those with children under six pay slightly higher prices for milk, possibly due to time constraints.

Various products incorporating single aspects of organic production systems such as lower inputs of pesticides, food additives or concentrated animal feed are found on the food market (referred to as low-input products hereafter). In our study, we analyzed how consumers react to low-input products in a purchase simulation with certified organic, conventional and low-input products. In the purchase simulations, each participant was asked to make three consecutive purchase decisions, one each for milk, yogurt and apples. The results of a cluster analysis revealed one cluster with a high preference for organic products and three clusters that featured considerable shares of low-input purchases. The latter clusters, however, were not characterized by a clear preference for low-input products. Rather, they bought mixed baskets of goods, i.e., low-input products in combination with either organic or conventional products. The low-input products in the categories milk, yogurt and apples did thus not necessarily attract the same groups of people. Interestingly, we found that most consumers who chose low-input products in the simulations usually buy those particular products in conventional quality. We conclude that in our study, we found a heterogeneous group of low-input buyers. For the organic sector, communicating the various aspects of organic production might be a promising strategy for gaining new customers. The low-input products in the purchase simulation only featured one special attribute, whereas organic products incorporate several.

Understanding the response of soil quality indicators to changes in management practices is essential for sustainable land management. Soil quality indicators were measured for 2 years under established experiments with varying management histories and durations at four locations in New York State. The Willsboro (clay loam) and Aurora (silt loam) experiments were established in 1992, comparing no-till (NT) to plow-till (PT) management under corn (Zea mays L.)–soybean (Glycine max L.) rotation. The Chazy (silt loam) trial was established in 1973 as a factorial experiment comparing NT versus PT and the crop harvesting method (corn silage versus corn grain). The Geneva (silt loam) experiment was established in 2003 with vegetable rotations with and without intervening soil building crops, each under three tillage methods (NT, PT and zone-till (ZT)) and three cover cropping systems (none, rye and vetch). Physical indicators measured were wet aggregate stability (WAS), available water capacity (AWC) and surface hardness (SH) and subsurface hardness (SSH). Soil biological indicators included organic matter (OM), active carbon (AC), potentially mineralizable nitrogen (PMN) and root disease potential (RDP). Chemical indicators included pH, P, K, Mg, Fe, Mn and Zn. Results from the Willsboro and Aurora sites showed significant tillage effects for several indicators including WAS, AWC, OM, AC, pH, P, K, Mg, Fe and Mn. Generally, the NT treatment had better indicator values than the PT treatments. At the Chazy site, WAS, AWC, OM, AC, pH, K and Mg showed significant differences for tillage and/or harvest method, also with NT showing better indicator values compared to PT and corn grain better than corn silage. Aggregate stability was on average 2.5 times higher in NT compared to PT treatments at Willsboro, Aurora and Chazy sites. OM was also 1.2, 1.1 and 1.5 times higher in NT compared to PT treatments at Willsboro, Aurora and Chazy sites, respectively. At the Geneva site WAS, SH, AC, PMN, pH, P, K and Zn showed significant tillage effects. The cover crop effect was only significant for SH and PMN measurements. Indicators that gave consistent performance across locations included WAS, OM and AC, while PMN and RDP were site and management dependent. The composite soil health index (CSHI) significantly differentiated between contrasting management practices. The CSHI for the Willsboro site was 71% for NT and 59% for PT, while at the Aurora site it was 61% for NT and 48% for PT after 15 years of tillage treatments.

No-tillage (NT) organic vegetable production presents several economic opportunities for growers in the southeastern United States while promoting natural resource conservation. This study was conducted to determine if removal of sorghum sudangrass (SS) cover crop biomass as hay, frequency at which the cover crop is mowed, and tillage affect weed suppression and head weight of transplanted organic cabbage. Sorghum sudangrass [Sorghum bicolor (L.) Moench×Sorgum sudanense (Piper) Staph.] was planted in May 2004 at Reidsville and Goldsboro, NC, preceding the planting of organic ‘Bravo’ cabbage (Brassica oleracea L. Capitata group) in August and September 2004, respectively. SS management systems included: low-frequency mowing with hay removed following the first mowing operation (LFM-H), low-frequency mowing with hay not removed (LFM), high-frequency mowing with hay not removed (HFM) and a no cover crop control. Two tillage treatments were applied within each management system: conventional tillage (CT) and NT. Under NT conditions, SS mulch generated by LFM offered broadleaf weed control in cabbage similar to that achieved under CT, regardless of whether cover crop biomass was removed as hay. Mowing with higher frequency reduced SS cover crop biomass by 18–33% and reduced weed suppression in NT cabbage. Mowing frequency did not influence the quantity of SS that re-grew in the cabbage crop. SS re-growth contributed to lower head weight in NT compared to CT cabbage in Goldsboro, and crop failure of NT cabbage in Reidsville. Cabbage head weight was highest when the crop was not preceded by SS in both CT and NT systems (1.6 as opposed to 1.3–1.4 kg head−1). Our findings suggest that the potential for growers to manage a cover crop also as a hay crop does exist; however, SS may not be a compatible cover crop species for organic fall cabbage production due to high amounts of re-growth.

Conventional agriculture often aims to achieve high returns without allowing for sustainable natural resource management. To prevent environmental degradation, agricultural systems must be assessed and environmental standards need to be developed. This study used a multi-factor approach to assess the potential environmental impact risk of six diverse systems: five production systems and a successional system or abandoned agronomic field. Assessment factors were soil quality status, amount of pesticide and fertilizer applied and tillage intensity. The assessment identified the best management practices (BMP)–conventional tillage system as a high-risk system mostly because of extensive tillage. The certified organic system was also extensively tilled and was characterized by P build-up in the soil, but performed well based on other assessment factors. Conversely, the BMP–no tillage and the crop–animal integrated system were characterized as low risk mainly because of reduced tillage. The paper discusses assessment strengths and weaknesses, ways to improve indicators used, and the need for additional indicators. We concluded that with further development the technique will become a resourceful tool to promote agricultural sustainability and environmental stewardship and assist policy-making processes.